US 2584271 A
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Patented Feb. 5, 1952 STEROID DERIVATIVES AND METHOD FOR PRODUCING THE SAME Max N. Hufiman, Dallas, Tex., assignor to G. D.
Searle & 00., Chicago, 111., a corporation of.
Illinois No Drawing. Application June 19, 1948,
. Serial No. 34,144
25 Claims. (Cl. 260-23955) This invention relates to compounds of the cyclopentanopolyhydrophenanthrene series and processes for manufacturing the same. More particularly, it relates to the partial synthesis of the 3, 16, 17-triol derivatives of the estrogen and androgen series of compounds and to the new intermediates which are produced in the synthesis. I
The products of this invention have certain physiological activity and they may be used primarily to supplement the hormones naturally produced in the human body. Because of the possibility of activating various positions of the steroid nucleus and providing various functional groups on those activated positions, it is conceivable that new compounds unlike the natural occurring hormones may be synthesized and used internally to impart physiological activity of a desired and predetermined character. Compounds of the type produced by my invention may also be used as chemical intermediates for the production of other cyclopentanoperhydrophenanthrene derivatives.
It is an object of this invention to eflfect the partial synthesis of esteriol, androstenetriol, and other 3, 16, 17-trio1s of the estrogen and androgen series and to provide a method for'producing the same.
Another object of this invention is to produce and to provide a method for manufacturing the a ketols of 3, 17-diol derivatives of the estrogen and androgen series of compounds including the corresponding 3-alkyl ethers, such a A -androstem-3(5), 17(a)-diol16-one-3-alkyl ether in which the alkyl group may be methyl, ethyl, propyl, benzyl, and the like; the 16, l'l-hydroxy derivatives of the estrogen and androgen series of compounds including estriol, isoestriol-A, the I-Iirschmann triol, and the like; the derivatives of 16, l'l-hydroxy estrogen and androgen series of compounds including the cyclic acetal of lsoestriol-A, isoestriol acetonides; and the .alkyl ethers of the 16, l'l-dihydroxy estrogen and androgen series of compounds, such as A -androstene-3(fi), 16(5), '1'7(a)-triol-3-a1kyl ethers including A -3(p), 16(5), 17(a) -triol-3-methyl ether and other derivative ethers in which aliphatic, aromatic, and mixed aliphatic-aromatic groups are substituted for methyl. f
A further object is to provide a method for converting 16-oximino steroid derivatives, such as, compounds of the estrogen and androgen series having a functional oxygen containing group on the C3 and C17 positions, to the corresponding a ketols (vicinal ketols) or 16, 17 ketols by a reduction process; converting the estrogen and androgen series of compounds having at least one ketone group in the 16 and 1'? positions and a hydroxy group in the other if only one of the positions is ketone to the corresponding 16, 1'1- hydroxy derivatives by a reduction process which does not giverise in large proportions, to a 16, 17 configuration differing from that of the natural occurring estriol; separating the cisoid and transoid 16, 1'7-hydroxy derivatives of the estrogen and androgen series of compounds; and the dealkylation of the 16, 17-hydroxy-3-alky1 ethers of the estrogen and androgen series of compounds and the conversion thereof to the correspending triols.
By the term fcyclopentanopolyhydrophenanthrene compounds, as used herein, it is meant the group of substances based upon the following nucleus,
R may be hydrogen in which the rings A, B, C, and D may either be saturated or unsaturated and in which some of therings, such as rings A and B may have as much three unsaturated groups to comprise gen compounds, androsterone (3(c)-hydroxy- 17 keto-androstane), dehydroisoandrosterone (3(a) -hydroxy-17-keto A -etioallocholene), and androstenedione (3, 17-diketo-etioallocholene).
In accordance with this invention, I may start with any of the compounds of the type named above having a ketone group in the functional C17 position. The C3 position may be allowed to remain hydroxy, but it is better to replace the hydroxyl by a group which is later reconvertible into hydroxyl. Representative of such replacement groups are the alkyl ethers in which the alkyl group is interpreted to include methyl, ethyl, propyl, and the like aliphatics, benzyl, naphthyl, and the like aromatics or mixtures thereof and derivatives thereof. Although my invention may be practiced by starting with one of the original materials described, inventive features of my invention commence by the reaction with the 16-oximino derivative of the corresponding steroid.
In the steps by which one of the compounds named above, such as estrone is converted to the corresponding 16-oximino derivative, the 3- hydroxy group may be etherified, that is, methylated by the process described by Butenandt, Stormer, and Westphal, Z. Physiol. Chem, 208, (1932). The corresponding 3-alkyl ether may then be nitrosated to give the 16-oximino derivative by the process of Litvan and Robinson, Journal of the Chemical Society, p. 1997 (1938).
In carrying out my invention, the lfi-oxlmino derivative of the corresponding steroid is carried through a reduction reaction by which the vicinal u. ketol derivative is produced. The a ketol in crude or purified form is then subjected to another reduction reaction to produce the a glycolderivative, hereinafter referred to as the corresponding 16, 17-hydroxy steroid. This includes 16, l'l-hydroxy steroids in which the 3 position is either hydroxy or otherwise modified, such as by an alkyl ether group. This last reduction step ordinarily results in the production of two isomeric a glycols; namely, the transoid 16(5), 17(11) -hydroxy steroid and the c'isoid 1'6(a), 17(a) hydroxy steroid. If desired, these may then be separated. I have conceived two processes by which these isomers may be separated. One includes a fractional crystallization process from solvent solution. The other requires a reaction of the isomeric mixture with a substance'which forms the derivative of only one enabling it to be separated from the other by such means as selective solvency. Each of the compounds resulting from the latter process may be reconverted to their original 16, 1'7-hydroxy form. When the active C3 position has been protected by an ether group, the a glycol may be dealkylated to produce the corresponding triol.
The 16-oximino or isonitroso steroid may be reduced to the corresponding a. ketol by the Stodola reduction, Stodola, Kendall, and Mc- Kenzie, Journal of Organic Chemistry, 6, 841 (1941). Briefiydescribed, the process includes the reaction of the 16-oximino steroid derivative with zinc dust in the presence of an organic acid, such as acetic acid, which may or may not be diluted with water. Upon evaporation of the separated liquid phase, a crystalline a ketol is produced which may be used as is, such as in the subsequent production of the corresponding triol synthesis, or the product may be purified by extraction with solvent, such as an ether dilute alkali solution. The ether phase may be washed by one or more of the compositions including dilute mineral acids, such as hydrochloric acid, dilute metal alkali bicarbonates, such as sodium bicarbonate, or water.
It is by this method that I have succeeded in producing compounds such as A -androstene- 3(13), l7(a)-diol-l6-one and A androstene-3(fi), 17(a)-diol-l6-one-3-alkyl others, such as the 3-methyl ether, 3-ethyl ether, B-benzyl ether, and the like To the best of my knowledge, these alkyl ethers have not-heretofore been produced by natural glandular secretion or by synthetic processes.
A salient feature of this invention resides in the use of a metal amalgam to effect the reduction of the a. ketol to the corresponding 16, 1'7- hydroxy steroid which may be a triol if C3 is hydroxyl or a glycol if the C3 position is otherwise modified, such as by an alkyl ether. When the reduction from the a ketol is carried out by hydrogen in the presence of a catalyst, the product is undesirable because it consists essentially of isomers of a 16, 1'7 configuration which differs from that of the natural occurring triols, such as estriol. Excellent yield of 16, 17-hydroxy steroids of the desired character is secured when the reduction is carried out with a metal amalgam, preferably in the presence of a hydrogen donor and at a temperature below 50 C. As the metal amalgam, I make use of mercury in combination with one of the base metals, such as sodium, zinc, magnesium, and the like. reaction, an excess of. the metal amalgam at relatively low concentration, such as about 2 percent, is used. Suitable hydrogen donors for use in the above reaction include inorganic or organic acids, bases, and neutral molecules of the type water and alcohol. As the hydrogen donor, I prefer to use a substance in which the steroid derivative is soluble. One such composition from which I have obtained excellent yield consists essentially of alcoholic acetic acid and freshly prepared sodium amalgam of about 2 percent concentration. Excellent yields of the desired glycols are secured when the reduction reaction is carried out at a temperature of about 4.041 C. or less. When higher temperatures are used, and especially when temperatures in excess of 50- C. are used, lower yields of the desired transoid derivative are secured.
Refinement of the 16, 1'7-hydroxy steroid resulting from the reduction process may be ef fected by extracting the reaction product with water and a suitable water immiscible solvent in which the steroid derivative is soluble, such as most of the higher molecular weight liquid alcohols, including butanol and the like, esters, such as ethyl acetate, amyl acetate, and the like, and ethers, such as ethyl ether, propyl ether, etc. A suitable solvent system, for example, comprises water and ethyl ether. The separated ethereal phase may be subsequently extracted with water and/or dilute alkali solutions, such as a sodium hydroxide solution, before evaporation of the ether, to crystallize the resultant l6, I'T-hydroxy steroid derivatives.
Another feature of this invention resides in the novel methods by which the two isomers of 16, I'Z-hydroxy steroids, that is, the cisoid and transoid isomeric substances, may be separated one from another. A mixture of these isomers is usually produced by the described metalamalgam reduction. One isomerwhich is produced in r ater preport qn when the reduction reap- In the tion temperature is held below 50 0. is the transoid 16(5), 17((1) -hydroxy steroid. The other less desirable is the cisoid 16(c), 17(00- hydroxy steroid. j
I have found that the transoid may be rather completely separated from the cisoid by the process of fractional crystallization from solvent solution, especially when the 3 position is alkylated. Because the transoid is less soluble than the cisoid in non-polar or relatively non-polar solvents, it may be separated from the cisoid by one or more recrystallizations from non-polar solvent systems. The ordinary hydrocarbons, such as the petroleum distillates, coal tar distillates, including petroleum ethers, Skellysolve. cyclohexane, toluene, benzene, butane, and other aliphatic and alicyclic solvents, and the like are examples of non-polar solvents. Ordinarily, an organic liquid compatible with the non-polar solvent and in which the steroid derivative is soluble is incorporated into the solvent system to control'the degree of solvation. I may make use of alcohols, ketones, ethers, dioxanes, and the like for the latter component. I prefer to use a solvent component which has a lower boiling point or greater volatility than the non-polar constituent of the solvent system to enable partial removal thereof from the solvent system when desired. One suitable solvent system with which I have obtained excellent results makes use of acetone and cyclohexane or Skellysol-ve.
When the 3 position is unalkylated, or phenolic, the transoid may be separated, by another method, from the cisoid by subjecting the mix ture to an acetal forming medium to form the cyclic acetal of the corresponding cisoid 16(11), 17(a) -hydroxy steroid. The transoid derivative which is substantially unreacted by the acetal forming medium may then be separated from the cisoid cyclic acetal by ordinary selective solvent means. A single solvent system may be used in which the tolerances for the cisoid acetal and the transoid a glycol are of a different order enabling separation by fractional crystallization.
A two component solvent system may be employed in which the selective solvent principle operates to concentrate one derivative in one phase and the other derivativein the remaining phase which is separable from the first. The latter system may include an aqueous alkaline phase in which the transoid derivative concentrates and an immiscible organic solvent phase for the ci'soid cyclic acetal, but in this event, it is desirable that the 3 position be phenol. For example, when the latter system is used, the transoid is found in high concentration in the solvent component containing an aqueous base solution, such as a dilute sodium hydroxide, potassiumhydroxide solution, and the like. The alkaline phase, which is separable from the solvent phase, may be extracted with a solvent for the cyclic acetal to extract any traces thereof. The aqueous hydroxide phase may then be acidified to produce the corresponding triol. The solvent phase may be a solvent immiscible with the aqueous alkaline solution and in which the cisoid cyclic acetal is soluble. Representative of such solvents are the chlorinated solvents, ethers, ketones, and some of thearomatics. Chloroform, ether, ethylacetate, ethylene dichloride are specific examples. The glycol may be regenerated by hydrolyzation of the cyclic acetal.
As the acetal forming medium, ketones and aldehydes capable of reaction in the presence of catalyst, such as an acid, to effect the acetal re- [ill action may be used. Acetone, methyl ethyl ketone, and other ketonic solvents or other ketones represent suitable acetal forming com pounds; aldehydes, such as butyraldehyde, glyoxal, pyruvic aldehyde, and aldehydic solvents, such as benzaldehyde, may be used. Inorganic acids, represented by anhydrous hydrochloric acid or other halogenic acids, comprisecatalysts for the acetal reaction. I have secured excellent results by the use of an acetal forming system consisting of acetone, only a. small portion of which is first saturated with anhydrous hydrogen.
It is by the described method that I have succeeded for the first time in producing the cyclic acetal of isoestriol-A, such as isoestriol-A- acetonide, and other isotriol-A-acetonides of the estrogen and androgen series of compounds. I
It is by these methods that I have succeeded for the first time in preparing and isolating the 3- alkyl ethers of A -androstene-3Q8), 16$), 17(11) -triols including the 3-methy1 ether, the 3- ethyl ether, the 3-benzyl ether, and the like.
As previously pointed out, the a. glycols, such as the reaction products of the metal amalgam reduction, may be constituted with an alkoxy group, such as methoxy, at C3. -When desired, conversion to the corresponding triol may be effected by a simple de-etherification, such as by hydrolysis. When the C3 position may be either (a) or (B), as in the androstane series of compounds, ie,- methylation or dealkylation presents a very dimcult problem.
I have discovered a very novel reaction by which the methyl group may be easily. and smoothly replaced in quantitative yield by a group readily convertible to hydroxyl. I first form the diacetal by reaction of the glycol with acetic acid or acetic anhydride, then I react the diacetal with p-toluene sulfonic acid in the presence of acetic anhydride to substitute acetyl for the methyl group M03. The resulting demethylated steroid may be saponified insolvent solution by an alkali metal base and from which the triol may be regenerated by simple hydrolysis in acid medium. By way ofillustration. but not by wayof limitation, the following examples are given to illustrate the invention:
EXA PLE 1 The conversion of estrone (I) to estrone-3- methyl ether (II) The methyla-tion of estrone may be carriedout by the process of Butenandt, Stormer, and Westphal, as previously pointed out EXAMPLE 2 The conversion of e strone methyl ether (II) to l6-oasimz'no estrone-3-methyl ether (III) Y This nitrosation reaction. may be carried out according to the process described by Litvan and Roblnson,Journal Chemical Society," p.
'EXAMPLE'3 maintained at 45 until solution of the steroid derivative was complete. Then 9.4 cc. of water was added and the solution refluxed for 1 hour 10 minutes and cooled to room temperature. The aqueous acetic acid solution was decanted from the zinc, and the latter washed with 100 cc. of benzene; To the combined aqueous acetic acidbenzene solutions were added 80 cc. of. 1.5 N sodium hydroxide and 200 cc. of ethyl ether. After having been partitioned and separated, the organic phase was washed successively with 0.5 N hydrochloric acidywith percent sodium bicarbonate, and with water. Evaporation of the ethereal solution yielded a crystalline product which, afterjtreatment with charcoal, was recrystallized once from cyclohexane and once from aqueous ethanol to give 207 mg. of needles melting at 164-165" C. Another treatment with charcoal and recrystallization from aqueous acetone raised the melting point to 167-168 (203 mg). The latter purification step may be dispensed with in the event that the crude reduction product. is suitable for use or'for further reaction as desired. I
EXAMPLE 4 Reduction of 16-keto-17(a)-hydr0a:yestratrienol- 3 -methyl (IV) to 1'6,'17-dihydroa:y estratrienol- 3-methyl ether (V) A solution of 800 mg. of the a ketol methyl ether in 100 cc. of ethanol and cc. of acetic acid was carefully maintained at (water bath), and 200 gm. of freshly prepared sodium amalgam (2 percent) were added in small pieces with efficient swirling. Before all of the amalgam had been added, a precipitation of sodium acetate occurred, and at this point an additional 100 cc. of percent acetic acid were added. After all the reducing agent had been added, the mixture was transferred to a separatory funnel with ether and water. The mercury plus aqueous phase was separated, after partitioning, from the ether; the latter maybe further washed with water, with 0.5 N sodium hydroxide, and again with water to purify the a glycol. ration of the ethereal phase yielded a crystalline residue of the isomeric transoid 16(5), 17(a)-di hydroxy-steroid -3methyl ether and cisoid 16(a), 1'7 (a) -dihydroxysteroid-3-methyl ether.
EXAMPLE 5 Separation of the cisoid. from the transoid 16, 17 -".glycols of steroid-d-methyZ-ether(V) by fractional crystallization Separation was effected by fractional crystallization from non-polar solvents system. in which the transoid derivative was less soluble than the cisoid. To this end, the mixed a glycols was recrystallized twice from acetone-petroleum ether. In actual practice, I.diss0lve the mixture of isomers in acetone and then add about 2volumes of the non-polar petroleum ether. Since the acetone has a greater volatility than the petroleum ether, such as Skelleysolve B the former leaves the solution and at the point where crystallization is initiated, further evaporation is stopped and crystallization, such as by cooling, causes the desired separation.
EXAMPLE 6 Demethylation of estrioZ-3-methyl ether (V) to produce estriol (VIII) To a solution of 155 mg. of estriol-B-niethyl ether in 3 0c. of pyridine were added 3 cc. of
Evapoacetic anhydride; the phases were mixed well and left 48. hours at room temperature. The diacetate was then precipitated by the addition of cold water, and, after having been allowed to stand several hours, filtered, washed Well with water, and dried in vacuo.
The dry diacetate was then dissolved in 5 cc. of warm ac'etic acid, 5 cc. of freshly distilled hydriodic acid (sp. gr. 1.7) were added, and the solution of diacetate methyl ether refluxed at once over a free flame. After exactly 5 minutes refluxing 100 cc. of cold aqueous sodium bisulflte were added and the resulting phases mixed well. After precipitation had become complete (ice box) ,the crystalline steroid was filtered, washed with aqueous sodium bisulflte, and then washed well with water. The residue'was dried in vacuo.
The demethylated estrogen was then dissolved in 25 cc.'of ethanol (room temperature) and a small spatula end of sodium hydrosulfite added. To the alcoholic solution were next added, for purpose of saponiflcation, 25 cc. of 1 N sodium hydroxide, and the latter was mixed with rapid swirling. The resulting solution at first became colored a deep yellow but soon turned almost col- N sodium hydroxide. The combined sodium hydroxide phases (400 cc. of 0.5 N) were acidified with concentrated hydrochloric acid and extracted with 500 cc. of ethyl ether. This ether, after separation from the aqueous acid phase, may be further washed withbicarbonate and with water; a crystalline residue of estriol resulted on its evaporation. The crystalline residue (after treatment with charcoal) may be recrystallized once from aqueousethanol to give estriol.
EXAMPLE 7 Reduction of 16-oa:i1nin0dehydroisoandrosterone V 3-methyl ether (IX) to A androstene-3(,B),
17(a) -diol- 1bf-one-3-methyl ether (X) To 500 mg. of 16-oximinodehydroisoandrosterone 3.-methy1 ethe'r were added 34 cc. of 50 percent acid, with 1.0 N sodium hydroxide, and with Water. Evaporation of the ethereal phase yielded a white crystalline product, A -androstene-3(fi), 17 (a) -dio1-16-one-3-methyl ether.
EXAMPLE 8 Reduction of A andr0stene-3(B), 17 (a) -diol-16- one-3-methyl ether (X) to M-androstene-Mfi), 16(5), '17(a)-trioZ-3-methyl ether (XI) by sodium amalgam To-the solution of the a ketol, of Example 7, in 58 cc. of ethanol and 6.5 cc. of acetic acid were gradually added 125 gin. of 2 percent sodium;
amalgam, the temperature being carefully maintained at 40.0-49.5 by continuous swirling in a Water bath. (As "soon as sodium acetate commenced. to precipitate, 5.0 cc. of 50 percent acetic acid were added.) completed, the mixture of mercury and solution was diluted with water and extractedwith ethyl ether. After removal of the mercury and aqueous phases, the ether may be further washed with water, with 0.5 N sodium hydroxide, and again with Water. Evaporation of the ether yielded a white crystalline product. After recrystallization, twice from acetone-Skellysolve and once from-absolute acetone M-androstene-Mc), 16(5), 1701)- triol 3-methyl ether crystallized as the hemiliydrate in the form of tiny leaves. The cisoid derivative is to be found in the petroleum solvent.
EXAMPLE 9 Transformation of urinary androstenetn'ol 3- methyl ether (XI) to the triol (XII) To 301 mg. of the 3-methyl ether of Hirsch manns triol (M. P. 195-196) dissolved in cc. of dry pyridine were added 3 cc. of acetic anhydri'de. The two phases were mixed well and left 24 hours with occasional swirling. The diacetate was then precipitated by treatment with 200 cc. of ice water, and finally, after 3jhours inith e ice box, filtered and washed copiously with water.
To the air-dried diacetat'e (as above) were add- When the reaction had beenv -50 cci of water.
of the reaction bath was carefully maintained at 40.0-40.5. As soon as sodium acetate commenced to precipitate from the reaction mixture, 5 cc. of 50 percent acetic "acid was added. The supernatant fluid was decanted from the mercury (whenever the reactionis ended) and to it was added 50 cc. of water. From this mixture, the alcohol was .largely removed by distillation, and the water-rich phase further diluted with 7 After a day in the ice box, the isomeric glycols were filtered and dried. Any remaining ketonic material was removed from the glycol mixture by the use of Girards reagent or carboxy-methoxylamine in the usual fashion.
EXAMPLE 11 The separation of the cz'soid and transoid isomers of estriol The non-ketonic product of Example 10 was dissolved in cc: of acetone at room temperature and 5 cc. of acetone saturated with anhydrous hydrogen chloride was added. This acetalforming medium was swirled for 5 minutes or longer and then added to 50 cc. of aqueous potassium carbonate (containing 1.50 g. of K2003), mixed at once, and then further diluted to a volume of 400 cc. with water. After a day in the ice box, the precipitated material was filtered, washed with water containing a trace" of pyridine, and then dried in vacuo. The dried residue, containing the'cisoid as the acetal, was then dissolved in 300 cc. of chloroformandpartitioned ed 186 mg. of p-toluene-sulfonic acid monohydrate and the solid materials covered with 18.6 cc. of redistilled acetic anhydride. The mixture was heated on the steam bath with frequent stirring for exactly 30 minutes and then cooled in an ice bath. As no crystallization of triacetate hado'ccurred within S'hours time, the anhydride was decomposed with ice water and the steroid extracted with ethyl ether. washed with aqueous sodium bicarbonate and with water, was dried and thenevaporated to produce. the triacetate. The resulting white residue may be recrystallized from aqueous ethanol (one time with the aid of charcoal) to yield 249 mg.
of white plates, M. P. 183-185".
then filtered and washedf' well Witrmater1 1qg mg., melting at 250-252"). The material-may be recrystallized once from aqueous ethanol, once from absolute acetone, and again? fron'i'v aqueous ethanol to produce the triol crystallized'ashex agonal plates with one-half molecule of water.
EXAMPLE 10 The sodium amalgam reduction. of IIi-Iceto-aestradiol (XIIDJto estriol (VIII) To a solution of vOA l gQof l6-lieto-aeestradioli in 50 cc. of 95 percent ethanol plus 5 .cc'..of ace.- tic acid were graduallyadded 100g. of 12 percent sodium amalgam, with the; application vofc'con'itinuous and efificient mixing. Thatemperature.
The-ether, after having been with 300 cc. of 0.1 N sodium hydroxide. The alkaline phase, containing the transoid as the alkali metal hydrate, was separated and again washed with 300 cc. of chloroform. The sodium hydroxide phase was then acidified with hydrochloric acid and extracted with ethyl ether. Evaporation of the ethereal phase yielded estriol, which may be recrystallized to any stage of purity desired. From the combined chloroform washings containing the cylic acetal of the cisoid derivative may be obtained isoestriol-A acetonide (XIV) (M. P. 183.5-184.5). Mild hydrolysis XXV) of isoestriol-A acetonide gives pure isoestriol-A EXAMPLE 12 The reduction of 16klQa-St7*ddi0l (XIII) to estriol by magnesium amalgam To a solution of485 mg. of l6-ket0-aestradiol in 50 cc. of ethanol cooled in an ice-water bath was added '76 g. of magnesium amalgam (4 g.
' Mg: '72 g. Hg), then gradually over the course of 1 hour was addedZO cc. of aqueous acetic acid l5 parts HOAc 13.5 parts H2O) in" ly'cc'. portions. Temperature was not allowed to exceed 50. After the reaction was ended, themixture was transferred to a separatory funnel using 800 cc. dilute hydrochlori'cjac id a'nd809 c'c. of'ethyl ether. After having been p'artition'e' was separated and washed again with' dilute hy drochloric acid and with water. Evaporation of the ether yielded'estriol. This'may be further treated by the processes of Examples 11 or 5 to separate estriol from isoestriol-A.
The reactions maybe illustrated by the following formulae which show the-various configura tions described. v 1
It will be understood that many changes and variations in materials, concentrations; and
conditions may be made by those skilledin the art accordance with the principles set forth tion as claimed.
he ether" CH: OH: CH:' 0 0 0 1| I NOH' HO HaC-O I I: III
ZnlHAc CH: CH: CH:
OH' OH OH -V q ,7 mc-o VIII v CH3 CHI CH3 0 OH OH on, A OH: H:
= NOH' T T Zinc, V ij Nan. HA 11+ om-o ens-0 0111-0 xx x x: l
CH3 CH; CH;
OH OH OH CH: 5 0 on i Ton MaHo H0 H0 H0 xm VIII CH: CH;
, \C/ 0 R, Ton
HOH A00 HO XIV V xv I claim as my invention:
1. A process for the manufacture of 16, 17-dihydroxy steroids of the androgen and estrogen series, wherein the corresponding steroid having a ketone group in at least one of the Cisand C17 positions and a hydroxyl group in the other is reduced by a base metal amalgam in the presence of a hydrogen donor.
2. In the process for the manufacture of 16, 1'7- dihydroxy steroids of the androgen and estrogen series, the reduction of the vicinal ketol of the corresponding 17((1) hydroxy steroid with a metal amalgam at a temperature below 50 C. and in the presence of a hydrogen donor.
3. The process, as claimed in claim 2, in which the hydrogen donor is selected of the group consisting of acids, bases, water and alcoholsc.
4. The process, as claimed in claim 2, in which the-hydrogen donor is dilute alcoholieacetie acid;
5. The process, as claimed in claim 2, in which the metal amalgam is sodium amalgam.
6. The process, as claimed in claim 2, in which as the starting material M-androstene-Bfli),
17(a.)-di0116-0I18-3 alkyl ether is employed.
7. The process, as claimed in claim 2, in which the reduction reaction is carried out at a temperature of about 40 .C. v
' 8. The process, as claimed in claim 2, in which the starting material is androstane-3(fi), 17(01)- diol-16-one.
9. In the process for the manufacture of transoid 16(5), 17(a) -dihydroxy steroids and cisoid 75, 16(0), 17 (a) -dihydroxy steroids, the separation of the transoid and the cisoid from a mixture produced by the reduction with metal amalgam of a steroid having a ketone group in at least one of the 16 and 1'7 positions and a hydroxy group in the other by dissolving the product in a non polar solvent system, the transoid being less soluble in the non polar solvent system than the corresponding cisoid, and decreasing the tolerance for the transoid in the solvent system to crystallize the transoid from solution in advance of the cisoid.
10. In the process for the manufacture of tran soid 16(p), 17(a)-dihydroxy steroids and cisoid 16(42), 17(a) -dihydroxy steroids, the separation of the transoid derivative and the cisoid derivative from a mixture produced by the reduction with metal amalgam of a steroid having a ketone group in at least one of the 16 and 17 positions and a hydroxy group in the other, reacting the reduction product with an acetal forming medium to generate the cyclic acetal of the cisoid derivative, .1
tive is less soluble than the corresponding cisoid,
and decreasing the tolerance for the transoid derivative in the solvent system by increase of the ratio of the non polar solvent relative to the solvent for the mixed derivatives, thereby to precipitate the transoid derivative from solution in advance of the cisoid.
12. The process, as claimed in claim 11, in
which the solvent system is composed essentially of a mixture of a non-polar solvent selected from the group consisting of aliphatic, alicyclic, and mixed aliphatic-aromatic hydrocarbons having relatively no functional groups and a solvent for the reaction product which is miscible with and vaporizable at a lower temperature than the nonpolar solvent.
13. The process for separating the transoid and cisoid isomers of 16, 1'7-dihydroxy steroids of the estrogen and androgen series of compounds from mixtures thereof by reacting the mixture with an acetal forming medium to generate the cyclic acetal of the cisoid isomer, then separating the cyclic cisoid acetal from the unreacted transoid isomer by selective solvency.
14. The process, as claimed in claim 13, in which the acetal forming medium consists essentially of a compound selected from the group consisting of ketones and aldehydes which give the acetal reaction with hydroxal groups on the steroid derivative in the presence of a catalyst. 15. The process for separating the transoid and cisoid isomers of 16, 17 dihydroxy steroids of the estrogen and androgen series of compounds from mixtures thereof by treating the mixed isomers with an acetal forming medium to generate the cyclic acetal only, of the cisoid isomer and then treating the acetal reaction product with a two component immiscible solvent system in which the products of the acetal reaction separate according to their respective solvency in the immiscible components of the solvent system.
16. The process, as claimed in claim 15, in which the isomeric compounds are phenolic in the Ca position, wherein the solvent system is composed of an aqueous alkaline phase in which the transoid derivative concentrates and an immisci- 14 ble organic solvent phase in which the cisoid derivative concentrates.
17. The process, as claimed in claim- 16, in which the acetonide of the cisoid 16(a) 17(c) -dihydroxy steroid is recovered by separation of the organic phase from the aqueous alkaline phase, and evaporation of the organic solvent from the organic phase.
18. The process, as claimed in claim 16, in which the solvent system is composed of a dilute aqueous solution of an alkali base and a chlorinated organic solvent immiscible with the aqueous alkaline phase and in which the cisoid derivative is preferentially soluble.
19. The process, as claimed in claim 18, in which the transoid 16(5) 17 (a) -dihydroxy steroid is recovered from solution in the dilute aqueous phase by separation of the aqueous phase from the solvent phase, acidification of the separated alkaline phase and extraction therefrom by organic solvents.
20. In the process for manufacturing the 3. 16(6), 17(0.) -triol derivatives of the estrogen and androgen series of compounds in which the hydroxyl on C3 is protected by replacement with an ether convertible to hydroxyl, the reduction of the (a) ketol of the corresponding steroid with a base metal amalgam in the presence of a hydrogen donor at a temperature below 50 0., fractionating the product of the reduction reaction by selective solvency to separate the transoid 16(5), 17(-a)-dihydroxy derivative of the corresponding steroid from the cisoid 16(11), 17(a)-dihydroxy derivative of the corresponding steroid, and the de-etherification of the alkyl group on C3 into hydroxyl to produce the corresponding triol.
21. The process, as claimed in claim 20, in which fractionation follows subjecting the reduction reaction product to an acetal forming medium whereby only the cisoid is converted to the corresponding acetal whereby selective solvency separation may be effected by disposing the acetalization reaction product into a separable twophase system to separate the transoid in one and the cisoid acetal in the other.
22. The cyclic di (lower alkyl) acetals of A estratriene-3, 16a, 17a triol.
23. The acetonide of A estratriene-3, 16a, 17a. triol.
24. A androstene-3(fl), 16(3), 17(e )-triol-3- lower alkyl ether.
25. A androstene-3(p), 16(3), 17(u) -trio1-3- methyl ether.
MAX N. HUFFMAN.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number Name Date 2,353,808 Butenandt July 18, 1944 2,388,688 Hass Nov. 13, 1945 FOREIGN PATENTS Number Country Date 523,696 Great Britain July 19, 1940- 860982 France Oct. 15, 1940 OTHER REFERENCES Butenandt: Berichte 723, pages 417-424 (1939).
Stodola: Jour. of Org. Chem., 6, pages 841-844 (1941) Huffman et al.: Jour. Am. Chem. Soc. 66, pages 150-152 (1944).
Ruzicka: Helv. Chim. Acta 28, 1609-1612 (1945).